Methemoglobinemia and hemolysis after enteral administration of methylene blue in a preterm infant: relevance for pediatric surgeons.

A preterm infant had methaemoglobulinemia and hemolytic anemia after enteral administration of methylene blue. The dye was administered to exclude a tracheoesophageal fistula. Methylene blue is a noxious product, especially in neonates. It should be considered a potential cause of acquired methemoglobulinemia, even after enteral administration.